Final answer:
The correct term for the wasting away or no development of muscle is atrophy. It is often associated with various diseases, aging, and prolonged physical inactivity, leading to a decline in muscle mass and strength.
Step-by-step explanation:
The term for the wasting away or no development of muscle is known as atrophy. Muscle atrophy involves a decrease in muscle mass, which can occur due to various diseases and conditions such as cancer, AIDS (leading to cachexia), heart disease, liver disease, and also as a result of aging, a process known as sarcopenia. Moreover, prolonged periods of physical inactivity, like bed rest or space flight, also lead to atrophy of skeletal muscle. This condition is characterized by a reduction in the size and number of muscle cells, as well as their protein content.
Disorders of the Muscular System like Duchenne muscular dystrophy (DMD) can also cause progressive muscle mass loss. Increased physical activity, on the other hand, can help delay sarcopenia by adding structural proteins and cellular changes that mitigate the effects of muscle atrophy, thereby preserving muscle strength and quality of life.